Auxiliary tool handle

ABSTRACT

An auxiliary tool handle for attachment to the free end of a hand operable, rotatable tool comprises a body having a cavity therein for receiving a ratchet mechanism. A cover plate closes the cavity and covers the ratchet mechanism. The ratchet mechanism comprises a rotatable circular disc member having teeth about the periphery thereof and an axial extension projecting through the cover plate for insertion in a corresponding recess of the regular handle of a tool. A pair of pawl members are mounted in the cavity of the body and are normally biased by springs into driving engagement with the teeth of the disc member. A pivoted cam member having an operating portion projecting through the cover plate is operative selectively to move either of the pawl members out of teeth engaging position to determine the direction of rotation of the body relative to the disc member.

' 581 Field oiSearch United States Patent Ballsmith et al.

[54] AUXILIARY TOOL HANDLE [21] Appl.No.: 855,581

[52] U.S.Cl ..l45/75,l45/61EA [51] Int Cl .B25g l/00, 825g 3/24 ..145/75, 77, 70, 50

[56] References Cited UNITED STATES PATENTS 1,456,692 /1923 Hargrave.....

[is] 3,654,975 [451 Apr. 11, 1972 Primary Examiner-Andrew R. Juhasz Assistant Examiner-Michael Koczo, Jr. Attorney-Ashlan F. Harlan, Jr.

[57] ABSTRACT An auxiliary tool handle for attachment to the free end of a hand operable, rotatable tool comprises a body having a cavity therein for receiving a ratchet mechanism. A cover plate closes the cavity and covers the ratchet mechanism. The ratchet mechanism comprises a rotatable circular disc member having teeth about the periphery thereof and an axial extension projecting through the cover plate for insertion in a corresponding recess of the regular handle of a tool. A pair of pawl members are mounted in the cavity of the body and are normally biased by springs into driving engagement with the teeth of the disc member. A pivoted cam member having an operating portion projecting through the cover plate is opera- 252090 12/1952 P? et tive selectively to move either of the pawl members out of 2720396 /1955 2 teeth engaging position to determine thedirection of rotation 1,619,043 3/1927 Scherwer ..l/70 X f thev body relative to the disc memben 2,803,980 8/1957 Vogel ..81/ X 1 Claim, 4 Drawing Figures I I .i- I

AUXILIARY TOOL HANDLE BACKGROUND OF THE INVENTION The present invention relates to tool handles and particularly to supplementary or auxiliary handles for rotatable hand tools suchas screw drivers and nut-drivers. By the use of such auxiliary handles the maximum force which can be applied to the regular tool handles by the fingers of the user can be increased greatly. Further, by employing a suitable ratchet movement in the auxiliary handle, additional convenience of operation can be obtained.

In Fratz et al., U.S. Pat. No. 2,620,001, dated Dec. 2, 1952, there is described an auxiliary or supplemental handle for screw drivers or the like which somewhat resembles the device of the present invention. However, although there is mention in the patent of ratchet action by the auxiliary handle, no ratchet structure is shown or described.

SUMMARY OF THE INVENTION The auxiliary tool handle of the present invention, as hereinafter described, is adapted for attachment to a regular tool handle of a hand operable, rotatable tool and provides means for easily and conveniently rotating the attached tool and for increasing the force that can be applied to such a hand operable, rotatable tool.

The auxiliary tool handle of the invention is characterized by a ratchet mechanism housed therewithin and a shank projecting axially outwardly therefrom for insertion in the regular handle of a hand operable rotatable tool. The ratchet mechanism comprises a rotatable disc member having a plurality of teeth equally spaced about the periphery thereof. Two pawl members are provided for selective engagement with the teeth of the disc member. Either-pawl member is operative to effect rotation of the disc member in the same direction of rotation as the handle or to permit relative rotation therebetween on reverse rotation of the handle. With both pawl members engaged with the teeth of the disc member, the auxiliary tool handle will positively drive the tool in both rotational directions as a conventional tool handle with no relative rotational movement between the auxiliary handle and the tool.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view, partly in section, of an auxiliary tool handle according to the present invention shown attached to a tool of the screwdriver type;

FIG. 2 is a bottom plan view of the tool handle shown in FIG. 1;

FIG. 3 is a view similar to FIG. 2 with the cover plate removed to better illustrate the tool driving mechanism; and

FIG. 4 is an enlarged vertical sectional view taken on the plane of line 4-4 of FIG. 3.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring now in detail to the drawing, there is shown in FIG. I an illustrative embodiment of the auxiliary tool handle of the present invention, comprehensively designated 10, releasably secured in the free end of the handle 12 of a screw driver 14. Although the auxiliary tool handle of the present invention is particularly useful with a screwdriver, it should be understood that such auxiliary handles are not limited in use therewith, but have utility with various types of hand operable, rotatable tools such as gimlets, drills, taps, wrenches and the like.

Auxiliary handle 10 comprises a generally conically-shaped body 16 having a substantially flat face 18 and, preferably, a series of indentations 20 equally spaced about the periphery of body 16 for accommodating the fingers of the user, thereby facilitating gripping of the tool handle and increasing the ease of manipulation.

A cavity 22 is provided in body 16 for housing a ratchet mechanism hereinafter more fully described. The cavity 22 is closed by an annular cover plate 26 which is received in a recess 28 provided in the face 18 of body 16 and abuts against an annular shoulder 30 in cavity 22. Cover plate 26 is secured to the body 16 by a plurality of screws 32 extending through countersunk holes 34 in plate 26 and threaded into internally threaded sockets 36 fonned integral with body 16. The screws 32 have a head configuration confomiing to the countersunk holes 34, thereby fitting snugly therein. While three such screws and a corresponding number of sockets 36 are shown 0 for purposes of illustration, it is to be understood that any necessary or desired number may be used and that other suitable types of fasteners may be used in lieu of screws, if desired.

A generally circular recess defined by an annular wall 40 is provided adjacent the inner or closed end of cavity 22 for receiving a rotatable disc member 42, preferably coaxial with said handle, and having a flat base 44 in bearing contact against an annular bead 45. The latter is in the inner end of the recess and coaxial therewith. A plurality of teeth 46 are evenly spaced about the periphery of disc member 42. The ends of teeth 46 remote from base 44 are beveled as shown at 48 in Flg. 4 and terminate in a reduced diameter portion 50 of the disc member 42. A shank 52 of non-circular shape in cross section projects axially outwardly from the reduced diameter portion 50 of the disc member 42 and is adapted to be inserted in an opening of corresponding shape in the free end of a hand operable, rotatable tool handle. Although the shank 52 is preferably of substantially square shape in cross section as shown in FIGS. 2 and 3, it will be clear that the cross section thereof may take various non-circular shapes having a plurality of faces. The shank 52 is provided with a ball detent 54 in one of its faces adapted to coact with a depression or recess in the tool handle into which it is inserted.

The cover plate 26 is provided with a central opening 56 through which shank 52 and reduced diameter portion 50 of disc member 42 pass. An annular beveled shoulder 58 is provided about the periphery of opening 56 and conforms to the shape of the beveled ends 48 of teeth 46. Thus, the cover plate 26 while fitting snugly in recess 28 with the outer exposed surface thereof flush with the face 18 engages the beveled ends 48 of teeth 46 to hold disc member 42 in place against the head 45.

The ratchet mechanism referred to above comprises a pair of pivotable pawl members 60 and 60' provided in cavity 22 and engaging teeth 46. The pawls are supported on a horizontal ledge 62 extending partially about the cavity and control the direction of rotational movement of body 16 relative to disc member 42. Pawl members 60 and 60 are identical and interchangeable, the right hand pawl member as shown in FIG. 3 being indicated as 60' to distinguish it from the left hand pawl member. Each pawl member is provided with a body 64 having a tooth engaging portion 66 at one end and a rounded head 68 at the other end joined to body 64 by inclined surfaces. The heads 68 extend into arcuate recesses 72 provided in the wall of cavity 22. The inner ends of heads 68 remote from cover plate 26 are provided with pivot pins 74 (FIG. 4) received in cylindrical recesses 76 provided in the ledge 62. Pawl members 60 and 60' are confined for pivotal movement between the ledge 62 and the cover plate 26.

A pair of helical springs 78 and 80 are seated at their one ends in recesses provided in the wall of cavity 22, the other ends of the springs 78 and 80 hearing against the sides of pawl members 60 and 60 and biasing the same to tooth engaging positions as shown in FIG. 3.

A pivoted cam member 84 is located between the pawl members 60 and 60 and has a pivot pin 88 (FIG. 4) on its inner end received in a cylindrical recess 90 formed in the ledge 62. The other end of the cam member 84 is engageable with the inner inclined surfaces of pawl members 60 and 60 and is provided with knurled projection or button 94 extending, for operation, through an arcuate slot 96 provided in the cover plate 26, as shown in FIG. 2.

With reference to FIG. 3, cam member 84 is shown in the neutral position wherein both pawl members 60 and 60' are in tooth engaging position with the disc 42 and no relative rotational movement between the body 16 and the disc can occur. By rotating the cam member 84 clockwise, (as seen in FIG. 3) from the neutral position, the outer end thereof engages the inner inclined surface of pawl member 60' to pivot the same counterclockwise about its pivot pin 74 against the bias of spring 80 into a position out of engagement with the teeth 46. Then, rotation of body 16 of tool handle in a counterclockwise direction, as indicated by arrow A in FIG. 3, rotates the disc member 42 in the same direction due to the engagement of portion 66 of pawl member 60 with the teeth 46. The portion 66 bears against one of the teeth 46 and drives it in the same direction of travel as the auxiliary handle. Thus, the associated tool in which shank 52 is engaged is rotated in the same direction. Upon reverse rotation of body 16 in a clockwise direction, opposite to that of arrow A, disc member 42 remains stationary since the tooth engaging portion 66 of pawl 60 is repeatedly cammed out of engagement with the teeth 46 against the bias of spring 78 to permit body 16 to be rotated relative to disc member 42. Because of inherent friction between the parts, however, relative rotation may not occur unless some resistance is applied to the tool.

By moving cam member 84 clockwise with reference to its position in FIG. 3, the outer end thereof engages the inner inclined surface of the left hand pawl member 60 and pivots the same clockwise about its pivot pin 74 against the bias of spring 78 into a position where the portion 66 of the pawl is out of engagement with teeth 46. In such case, body 16 of the auxiliary handle 10, in rotating counterclockwise as indicated by arrow A in FIG. 3, carries along with it the pawl members 60 and 60' and the tooth engaging portion 66 of pawl member 60 thereof is repeatedly cammed out of engagement with teeth 46 against the bias of spring 80 to permit body 16 of auxiliary handle 10 to be rotated relative to disc member 42 and the tool attached thereto. Reverse rotation of body 16 in a clockwise direction opposite to that of arrow A rotates the disc member 42 in the same direction due to the bearing relation of pawl member portion 66 of pawl 60 with one of the teeth 46 of disc member 42. This results in rotating the tool with which auxiliary handle 10 is employed in the same direction.

The body 16 of auxiliary handle 10 is preferably formed of a heat setting, molded plastic material, such, for example, as a phenolic resin. The disc member 42, shank 52 and pawl members 60 and 60' are preferably formed of steel. It should be understood, however, that these elements as well as the other elements of the auxiliary handle may be formed of any suitable materials within the purview of this invention. Also, the handle 10 and shank 52 may vary in size as desired although the latter should be non-circular in cross section. As stated above, a square cross sectional shape is preferred. Although the body 16 is preferably of conical shape having evenly spaced indentations around the periphery thereof, the principles of this invention contemplate any suitable shape, with or without indentations, as desired.

It will be understood that the handles of hand operable, rotary tools with which the auxiliary tool handle of the present invention is used must be provided with recesses cooperable with the shank of the auxiliary handle for rotation thereby. Preferably such cooperating recesses are the same shape and size as the shank and may be conveniently provided by a metal thimble, such as is shown at 92 in FIG. 1, non-rotatably inserted in the tool handle.

As a result of the present invention, an auxiliary tool is provided for attachment to a hand operable, rotatable tool for easily and conveniently rotatiang the same in a desired direction with a ratchet effect. The use of the auxiliary handle of this invention eliminates the necessity of releasing and regripping the regular tool handle after each partial turn. Also, the force applied to the tool may be substantially increased without a corresponding increase of human effort.

A preferred embodiment of this invention having been hereinabove described and illustrated, it is to be understood that numerous modifications thereof can be made without departing from the broad spirit and scope of this invention.

We claim:

'1. An auxiliary tool handle comprising: a relatively thin, disc-like body having a cavity therein; a cover plate for closing said cavity; an annular bead in said cavity and axially spaced from said cover plate; a rotatable disc member supported between said cover plate and said annular bead in bearing contact therewith, said rotatable disc member having a plurality of teeth evenly spaced about the periphery thereof and having a portion projecting axially therefrom through the center of said cover plate for insertion in a cooperating recess in the handle of a tool; a supporting ledge in said cavity axially spaced from said cover plate and generally parallel thereto; a pair of pawl members supported between said ledge and said cover plate; spring means for normally biasing said pawl members into engagement with said teeth; and a cam member disposed between said pawl members and having a portion projecting through said cover plate and operable to pivot said cam member to selectively move said pawl members out of engagement with said teeth for controlling the direction of rotation of said body relative to said disc member. 

1. An auxiliary tool handle comprising: a relatively thin, disclike body having a cavity therein; a cover plate for closing said cavity; an annular bead in said cavity and axially spaced from said cover plate; a rotatable disc member supported between said cover plate and said annular bead in bearing contact therewith, said rotatable disc member having a plurality of teeth evenly spaced about the periphery thereof and having a portion projecting axially therefrom through the center of said cover plate for insertion in a cooperating recess in the handle of a tool; a supporting ledge in said cavity axially spaced from said cover plate and generally parallel thereto; a pair of pawl members supported between said ledge and said cover plate; spring means for normally biasing said pawl members into engagement with said teeth; and a cam member disposed between said pawl members and having a portion projecting through said cover plate and operable to pivot said cam member to selectively move said pawl members out of engagement with said teeth for controlling the direction of rotation of said body relative to said disc member. 